diff options
Diffstat (limited to 'src/mylloc.s')
| -rw-r--r-- | src/mylloc.s | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/src/mylloc.s b/src/mylloc.s new file mode 100644 index 0000000..9657b73 --- /dev/null +++ b/src/mylloc.s @@ -0,0 +1,50 @@ +;;# struct block { +;;# void *addr; // pointer to the start address of the block +;;# u32 size; // the size of the block +;;# void *next // pointer to the previous block +;;# }; +# +#;; .section .data +# +#;; ;;;# Constants +#;; .equ SYS_BRK, 214 +#;; .equ BLOCK_SZ, 12 +#;; .equ BLOCK_ARR_CAP, 1024 +# +#;; .section .bss +# +#;; system_break_start: +#;; .space 4 +#;; system_break_cur: +#;; .space 4 +# +#;; block_root: +#;; .space BLOCK_SZ +#;; block_arr: +#;; .space BLOCK_SZ * BLOCK_ARR_CAP +# +#;; .section .text +# +#;; .globl malloc +#;; .globl free +# +#;; malloc: +#;; mv t6, a0 ;# save the arg +# +#;; la t1, system_break_start ;# load the break +#;; la t2, system_break_cur ;# +#;; lw a0, 0(t1) ;# has the break been initialized +#;; bnez a0, block_loop ;# +# +#;; li a7, SYS_BRK ;# do brk syscall with an invalid arg +#;; ecall ;# to get the current break +# +#;; sw a0 0(t1) ;# save the break +#;; sw a0 0(t2) ;# +# +#;; block_loop: ;# in this loop find the first free address +# +#;; ret +#;; free: +#;; ret +# |